Do video game demos hurt sales of a game?

Something i was thinking about recently. I notice that almost all the times I download a demo for a game I end up never buying the actual game. It's not because the demos are bad but either the demo didn't sell me enough on the game or was satisfied with the demo to not need to buy the full version.

No I'm pretty sure they help. More times than not, the demo encourages more people to buy the game than it does deter people from buying it. I don't have any concrete stats on this but the mere fact that companies still put out demos makes me think that they work somewhat.

I find myself borderline on games a lot and I want a demo that I can play to get a feel for the game and see how well it will run on my pc. I have passed up a lot of games because I was borderline. I have bought many games that I was unsure about because the demo wow'd me.

If a demo satisfies me on the game or doesn't impress me... it's not the fault of it being a demo... it's the fault of the game being uninteresting to me. If I had bought the game for any reasonable amount of money and hated it, I'm pretty likely to never buy anything from that developer again. If I play a demo and it's just "meh" I will often continue to check out their stuff because I remember playing it. I also think it's a sign that the company stands behind their game that they are willing to let you sample it and that suggests a stronger title and a better developer.

So overall I think demos are a good thing and probably help sales of games. If they didn't, I would wager that they would have gone by the wayside long ago as we have had game demos around for decades now.

That's kind of a loaded question. It will hurt the sale of games that suck... but if you a play the demo for a well written (and well developed) game there's no way it could hurt sales. If anything, it would boost sales.

Depends on the game. If I play a demo that I have fun with, I usually buy the actual game. If I don't like the demo, I usually don't buy the game. I honestly think it depends on how the demo is set up.